1. Field of the Invention
The present invention relates to a multi-application execution system and to a storage medium.
2. Related Background Art
As shown in FIG. 9, in a multi-process execution environment, a memory space of each process is safeguarded by the execution environment, and hence it does not happen that parameters etc. are accessed by a different process without permission. As illustrated in FIG. 10, however, in a single-process/multithread execution environment as on Java(™) platform, the thread is not given a protection of the memory space unlike the process.
Further, normally only one application runs on a single virtual machine of Java(™). Therefore, in the case of scheming to execute a plurality of applications on a certain device, it is required that a plurality of virtual machines be executed. A built-in device is, however, hard to execute the plurality of virtual machines in terms of resources of the device.
What has therefore hitherto been practiced is an execution of the application on one virtual machine in a way that allocates the thread to every application.
In this case, however, each application runs on the same process, and hence the data within the application and system resources are not sufficiently protected.
Further, a Java(™) security manager, when a certain thread accesses a different thread, merely provides only a control framework as to whether this access should be enabled or not but does not, if a plurality of applications run on one virtual machine, provide any scheme showing what condition and how the application-to-application data and the system resources be protected and the access be enabled under.